Inconsistences in the harmonic analysis of time series


The power of asteroseismology relies on the ability to infer the stellar structure from the unambiguous frequency identification of the correspoinding pulsation mode. Hence, the use of a Fourier transform is in the basis of asteroseismic studies. Nevertheless, the difficulties with the interpretation of the frequencies found in many stars lead us to reconsider Fourier analysis and the classical methods used to process time series of pulsating stars observed from satellites. In this talk we will show two fundamental results: (1) the necessity of a method preserving the physical content of frequencies of the original function describing observations from satellites like CoRoT or Kepler, and (2) the time series of pulsating stars are originated from non-analytic signals. Therefore, the Fourier expansion of these signals is not guaranteed. We conclude, emphasizing the necessity of a new interpretation of the stellar light curves in order to identify the correct frequencies of the pulsation modes.

24/04/2014 - 14:30
Javier Pascual Granado